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Differential Upgrades
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Differential Upgrades
Thanks for the advice!
But darn it, I wish I'd not seen the vids of the cars running 3.91 diffs - looks like a super upgrade......!
More thinking / saving to do...!
But darn it, I wish I'd not seen the vids of the cars running 3.91 diffs - looks like a super upgrade......!
More thinking / saving to do...!
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- Senior Member
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Differential Upgrades
Who would you use to rebuild it / replace the seals?
Sepang Coupe
Imola Roadster - For sale
Interlagos Coupe - For sale
Previous:
Stratus Grey Coupe
Titan Silver 3.0 Roadster
Carbon Black Coupe
Silver Grey MR
Silver Grey 3.0si Roadster
Maldives Blue 2.5
Sterling Silver 3.0 - twice
Imola Roadster - For sale
Interlagos Coupe - For sale
Previous:
Stratus Grey Coupe
Titan Silver 3.0 Roadster
Carbon Black Coupe
Silver Grey MR
Silver Grey 3.0si Roadster
Maldives Blue 2.5
Sterling Silver 3.0 - twice
- BMWZ4MC
- Lifer
- Posts: 6342
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- Location: Back in the sunshine
Differential Upgrades
As testimony to the durability of the standard differential, I have used my ///M as a track car for nine years covering thousands of miles without any problems.
Z4MC - heavily fettled for track use
Lotus Exige - sensible daily driver on the mods slippery slope
Westfield SEiW - in hibernation
Modified RS4 Avant - back in Blighty
S2000 GT - gone
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- Newbie
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Differential Upgrades
http://www.jcracing.info/
In Thirsk
Speak to theses chaps as build loads of diffs for M3’s running in most race series throughout the U.K.
In Thirsk
Speak to theses chaps as build loads of diffs for M3’s running in most race series throughout the U.K.
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Differential Upgrades
Thanks All!
Looks like I'll be going for rebuilding the standard diff with a 3.91 ratio - watch this space...
Looks like I'll be going for rebuilding the standard diff with a 3.91 ratio - watch this space...
- Vanne
- Senior Member
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Differential Upgrades
Interesting..
2007 EuroSpec Z4///MC Building/Developing Z4 GT3
Powered by Severn Tuning
Powered by Severn Tuning
- exdos
- Senior Member
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- Joined: Wed Feb 22, 2012 12:58 am
Differential Upgrades
I did a diff ratio swap on my Z3MC in 2010 from OEM 3.15 to 3.46. When I did some datalogging from the ECU using various parameters, the swap didn't make any significant difference to on-road performance and just increased fuel consumption. For me, it was a waste of time/money and I went back to the OEM ratio.
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Differential Upgrades
Good to know Exdos - I'm still pondering this one...
- bradz
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- Location: Bedford
Differential Upgrades
I have just taken the plunge and purchased a Gripper 12 Plate diff & BMW 4.10 final ratio.
This is for my e46 M3 though (Track car)
After doing a bit of research is seams the 4.10 is the one to go for, Takes the top speed down to about 170 but it will get there pretty quickly! apparently its the equivalent of 40bhp
https://www.automac.co.uk are building mine.
Adam
This is for my e46 M3 though (Track car)
After doing a bit of research is seams the 4.10 is the one to go for, Takes the top speed down to about 170 but it will get there pretty quickly! apparently its the equivalent of 40bhp
https://www.automac.co.uk are building mine.
Adam
Z4M Coupe, E92 M3, E46 M3 Track car
- TomK
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- Location: West London
Differential Upgrades
Cool let us know how you get on with it! I've heard really good things about the gripper and been looking at the same solution, it makes a lot of sense in terms of performance and economics.bradz wrote: ↑Thu Dec 13, 2018 10:35 pm I have just taken the plunge and purchased a Gripper 12 Plate diff & BMW 4.10 final ratio.
This is for my e46 M3 though (Track car)
After doing a bit of research is seams the 4.10 is the one to go for, Takes the top speed down to about 170 but it will get there pretty quickly! apparently its the equivalent of 40bhp
https://www.automac.co.uk are building mine.
Adam
For me it'll be an 8 plate and the 3.91 cwp as my car is still supposed to be not too unpleasant on the road (think the 12 plate is a bit on the noisy side?).
MC[IB], CSL airbox, Schrick 288/280 cams, 4.44FD, UUC SSK, SS race cat back, AP CP9660[F]/5144[R] brakes, Apex ARC-8 with AR-1 or PS5, KW ClubSport 2-way, Turner spherical arms, PMC uniball rtab, VB engine mounts, Rogue pulleys & RSMs, Tillett B6, half cage
- bradz
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Differential Upgrades
Cheers I will do.
Automac who are building it said the 12 plate will be noisy at low speed on the road and will push the front at very low speed. (This was a concern of mine as I still drive to tracks & the ring) They said its not horrific and the way it hooks up on track will make it worth it, They also said when it goes in for its 12 month checkup if I wanted they could change it back to a 8 plate for no extra cost.
That was enough to persuade me to go all out!
Automac who are building it said the 12 plate will be noisy at low speed on the road and will push the front at very low speed. (This was a concern of mine as I still drive to tracks & the ring) They said its not horrific and the way it hooks up on track will make it worth it, They also said when it goes in for its 12 month checkup if I wanted they could change it back to a 8 plate for no extra cost.
That was enough to persuade me to go all out!
Z4M Coupe, E92 M3, E46 M3 Track car
- TomK
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Differential Upgrades
Can't argue with that! Keep us postedbradz wrote: ↑Thu Dec 13, 2018 11:44 pm Cheers I will do.
Automac who are building it said the 12 plate will be noisy at low speed on the road and will push the front at very low speed. (This was a concern of mine as I still drive to tracks & the ring) They said its not horrific and the way it hooks up on track will make it worth it, They also said when it goes in for its 12 month checkup if I wanted they could change it back to a 8 plate for no extra cost.
That was enough to persuade me to go all out!
MC[IB], CSL airbox, Schrick 288/280 cams, 4.44FD, UUC SSK, SS race cat back, AP CP9660[F]/5144[R] brakes, Apex ARC-8 with AR-1 or PS5, KW ClubSport 2-way, Turner spherical arms, PMC uniball rtab, VB engine mounts, Rogue pulleys & RSMs, Tillett B6, half cage
- GuidoK
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Differential Upgrades
Thats the result of a very blunt calculation.
Its the equivalent of 44bhp for 77% of the time and a loss of ~82bhp for 33% of the time.
Only when you're in the same gear you have the 44bhp advantage, but with the shorter gears you have to shift up earlier, resulting in much much less wheel torque (and equivalent power).
Its a difficult exact calculation to make. The powerpart when you're in the same gear its easy, but the percentage of time and drop in power when going in different gears is difficult because not every gear is equally spaced. For the percentage I took gear 1-3 (so thats accelerating up to 100mph on the standard final drive), and the loss in power when riding in a higher gear I took the difference between 2nd and 3rd gear (the loss in power between 1st and 2nd is bigger as the corresponding difference in gearing is bigger).
0-60 will be faster with the short ratio but 0-105 will be slower (and 0-90 will be quicker).
So it really depends on what exact speeds you try to reach.
But the +40hp gain is not true (well, its true for 77% just as the loss of ~82hp is true for 33%).
In the end the gain is 0%. The ratio that maximizes the end speed reached wins.
Z4 3.0i | ESS TS2+ | Quaife ATB LSD | Brembo/BMW performance BBK front/rear | Schrick FI cams | Schmiedmann headers+cats | fully polybushed | Vibra-technics engine mounts | H&R anti rollbars | KW V3 coilovers | Sachs Race Engineering clutch
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Differential Upgrades
Happy New Year everyone! I've just spoken with my local Indy and they are suggesting getting a standard diff rebuilt to standard spec is going to be tricky due to lack of parts availability. Not sure how true that is so any advice on that is much appreciated!
Just looking at the above, the gripper diffs are also a tempting option - is there a ballpark price for the build?? I'd probably keep the 3.64 ratio and something not too aggressive as the car is mainly used on the road.
It seems to me to be much easier to just swap the whole unit than have to go through the pain of taking the diff out and then have the car hanging about for weeks whilst the diff is sorted...
As ever, any advice is much appreciated!
Just looking at the above, the gripper diffs are also a tempting option - is there a ballpark price for the build?? I'd probably keep the 3.64 ratio and something not too aggressive as the car is mainly used on the road.
It seems to me to be much easier to just swap the whole unit than have to go through the pain of taking the diff out and then have the car hanging about for weeks whilst the diff is sorted...
As ever, any advice is much appreciated!
- R60BBA
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Differential Upgrades
Standard diff is good enough for road use.
If you want a track focused car then I recommend the BMW Motorsport 4:10 diff.
Darragh Doyle (ex F1 tech) @ Everything M3’s can rebuild a diff to your specification at a reasonable price.
Skip to 12 mins 40 sec:
Website: https://m.facebook.com/pages/category/C ... 713409262/
If you want a track focused car then I recommend the BMW Motorsport 4:10 diff.
Darragh Doyle (ex F1 tech) @ Everything M3’s can rebuild a diff to your specification at a reasonable price.
Skip to 12 mins 40 sec:
Website: https://m.facebook.com/pages/category/C ... 713409262/
Current: 2002 E46 M3
Current: 2005 997 Carrera S
Gone: 2004 R53 Cooper S
Gone: 1998 E31 840Ci Sport
Gone: 2007 Z4 E86 3.0Si Sport
Gone: 2001 Z3 E36/7 2.2i San Remo Individual
Gone: 2015 F21 116d M Sport
Gone: 2012 A3 Sportback 1.2TFSI
Current: 2005 997 Carrera S
Gone: 2004 R53 Cooper S
Gone: 1998 E31 840Ci Sport
Gone: 2007 Z4 E86 3.0Si Sport
Gone: 2001 Z3 E36/7 2.2i San Remo Individual
Gone: 2015 F21 116d M Sport
Gone: 2012 A3 Sportback 1.2TFSI